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From Discrepancy to Majority

  • David EppsteinEmail author
  • Daniel S. Hirschberg
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9644)

Abstract

We show how to select an item with the majority color from n two-colored items, given access to the items only through an oracle that returns the discrepancy of subsets of k items. We use \(n/\lfloor \tfrac{k}{2}\rfloor +O(k)\) queries, improving a previous method by De Marco and Kranakis that used \(n-k+k^2/2\) queries. We also prove a lower bound of \({n/(k-1)-O(n^{1/3})}\) on the number of queries needed, improving a lower bound of \(\lfloor n/k\rfloor \) by De Marco and Kranakis.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.Department of Computer ScienceUniversity of CaliforniaIrvineUSA

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